/* eslint-disable */
export var codeHandler = (function(){
  var base64Chars = [
    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
    'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
    'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
    'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
    'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
    'w', 'x', 'y', 'z', '0', '1', '2', '3',
    '4', '5', '6', '7', '8', '9', '+', '/'
  ]
  var encode = {
    'base64':codeBase64
  }
  var decode = {
    'base64':decodeBase64
  }
  var handleFormat = {
    'utf-8':toUTF8Binary
  }
  function stringToBinary(str , size , encodeType ){
      //  str-字符串 , size - 转换后的二进制位数 ,encodeType - 采用什么格式去保存二进制编码
      var i,
          len,
          binary = '';
      for ( i = 0 , len = str.length ; i < len ; i++ ){
          binary = binary + handleFormat[encodeType.toLowerCase()](str.charCodeAt(i));
      }
      return binary;
  }
  // 转换为以UTF-8格式的二进制数据
  function toUTF8Binary(unicode){
      var len,
          binary = '',
          star = 0,
          bitStream = unicode.toString(2), // 转换为二进制比特流
          bitLen = bitStream.length,
          i;
      if( unicode >= 0x000000 && unicode <= 0x00007F ){
          binary = bitStream;
          for( i = 0 , len = 8 ; i　< len-bitLen ; i ++ ){
              binary = 0 +binary; // 不足8位补0
          }
      }else if( unicode >=0x000080 && unicode <=0x0007FF ){
          binary = bitStream;
          for( i = 0 , len = 11 ; i　< len-bitLen ; i ++ ){
              binary = 0 +binary; // 不足11位补0
          }
          binary = '110'+binary.substr(0,5) + '10' + binary.substr(5,6);
      }
      else if( unicode >=0x000800 && unicode <=0x00FFFF ){
          binary = bitStream;
          for( i = 0 , len = 16 ; i　< len-bitLen ; i ++ ){
              binary = 0 +binary; // 不足16位补0
          };
          binary = '1110' + 
                   binary.substr(0,4) + 
                   '10' + 
                   binary.substr(4,6) + 
                   '10' + 
                   binary.substr(10,6);
      }
      else if( unicode >=0x010000 && unicode <=0x10FFFF ){
          binary = bitStream;
          for( i = 0 , len = 21 ; i　< len-bitLen ; i ++ ){
              binary = 0 +binary; // 不足21位补0
          }
          binary = '11110' + 
                   binary.substr(0,3) + 
                   '10' + 
                   binary.substr(3,6) + 
                   '10' + 
                   binary.substr(9,6) +
                   '10' + 
                   binary.substr(15,6);
      }
      return binary;
  }
  // 编码成base64格式
  function base64Parse(binary24,flag){
      var i,
          len,
          result = '',
          decode;
      if(flag == 1){
          for( i = 0 ; i < 4 ; i++){
              decode = parseInt(binary24.substr(i*6,6),2);
              result = result + base64Chars[decode];
          }
      }
      else{
          for ( i=0 , len = Math.floor(flag/6) ;i<len+1; i++){
              decode = parseInt(binary24.substr(i*6,6),2);
              result = result + base64Chars[decode];
          }
          for( i = 0; i < 3-len ;i ++){
              result = result + '=';
          }
      }
      return result;
  }
  // 解析为base64格式的二进制数据
  function codeBase64(str){
      var i,
          len,
          rem,
          mer,
          result = '',
          strBinaryAry = [],
          binary = stringToBinary(str , 8 , 'utf-8'); // base64是基于utf-8格式保存的二进制数据转换的
      len = binary.length;
      mer = Math.floor(len / 24);
      rem = len % 24;
      for( i = 0 ; i < mer ; i++){
          result = result +  base64Parse(binary.substr(i*24,24),1);
      }
      var remCode = binary.substr(len-rem,rem);
      if( rem > 0 ){
          for( i =0 ; i < 24-rem ; i++){
              remCode = remCode + 0;
          }
          result = result +  base64Parse(remCode,rem)
      }
      return result;

  }
  // 解码base64格式的数据
  function decodeBase64(str){
      var i,
          j,
          k,
          len,
          t = 0,
          curbinary,
          start  = 0 ,
          flag = [
              {
                  str:'0',
                  len:8
              },
              {
                  str:'110',
                  len:11
              },
              {
                  str:'1110',
                  len:16
              },
              {
                  str:'11110',
                  len:21
              }],
          binary= '',
          newStr = '';
      for( i = 0 , len = str.length ; i < len ; i++){
          var curbinary  = base64Chars.indexOf(str.charAt(i)).toString(2);
          if( curbinary != '-1'){

              for( j = 0 ; curbinary.length <6 ; j++){
                  curbinary = 0 + curbinary;
              }
              binary = binary + curbinary;
          }
          if( i >= len-2 && str.charAt(i) == '='){
              ++t;
          }
      }
      if( t == 0 ){
          len = binary.length;
      }
      else{
          len = binary.length - (6-2*t)
      }

      for( ; start < len ;){
          for( j  = 0 ; j < 4 ; j++){

              if(binary.indexOf( flag[j].str ,start) == start){
                  if(flag[j].len == 8){
                      newStr = newStr +  String.fromCharCode(parseInt(binary.substr(start,8),2));
                  }
                  else if(flag[j].len == 11){
                      newStr = newStr + 
                               String.fromCharCode(parsetInt(binary.substr(start+3,5) + 
                               binary.substr(start+10,6),2));
                  }
                  else if(flag[j].len == 16){
                      newStr = newStr + 
                               String.fromCharCode(parsetInt(binary.substr(start+4,4) + 
                               binary.substr(start+10,6) + 
                               binary.substr(start+18,6),2));
                  }
                  else if(flag[j].len == 21){
                      newStr = newStr + 
                               String.fromCharCode(parseInt(binary.substr(start+5,3) + 
                               binary.substr(start+10,6) + binary.substr(start+18,6) +
                               binary.substr(start+26,6),2));
                  }
                  start  =  start  + flag[j].len;
                  break;
              }
          }
      }
      binary = null;
      return newStr;
  }
  return {
      encode:function(str ,type){
          return encode[type](str);
      },
      decode:function(str, type){
          return decode[type](str);
      }
  };
})();